The present invention relates to an image processing device, an image processing method, an electronic instrument, and the like.
For example, the number of pixels and the number of grayscales per pixel of a liquid crystal display device of a portable telephone have been increased in order to display a high-definition image. A VGA mode (480×640 dots) or a WVGA mode (480×800 dots) is expected to be employed for the screen of a portable telephone instead of a QVGA mode (240×320 dots). The grayscale value per pixel is 16 or 18 bits in the QVGA mode. The grayscale value per pixel (definition) is increased to 18 or 24 bits in the VGA or WVGA mode. An increase in the number of pixels and the grayscale value requires an increase in capacity of a memory which stores image data.
An increase in capacity of a memory significantly increases the cost of a driver IC including a RAM. For example, the memory area of a RAM increases by four when employing the QVGA mode instead of the VGA mode, whereby the area of a driver IC (driver section in a broad sense) including a RAM increases to a large extent. In this case, a driver IC including a RAM which is mounted on a glass substrate using a chip on grass (COG) technology increases the area of a glass substrate of a liquid crystal display panel, whereby the number of panels produced from a production substrate decreases. Moreover, the rectangular shape of a known driver IC of which the longitudinal axis coincides with the short side of the glass substrate cannot be maintained. This makes it difficult to employ the COG mounting technology. Therefore, it is necessary to use a chip on film (COF) mounting technology.
Some portable telephones employ a configuration in which a liquid crystal control IC is provided between a baseband engine and a liquid crystal driver IC in order to reduce the task of the baseband engine relating to liquid crystal display instead of a configuration in which a baseband engine (LSI) directly supplies image data to a liquid crystal driver IC. However, the capacity of a memory provided in the liquid crystal control IC must be increased as the amount of image data increases.
The above problem also occurs when transferring high-definition image data between an integrated circuit (image output source) which receives or generates and image and an integrated circuit which drives a display section or a printer.
In recent years, an image captured using a camera provided in a portable telephone may be displayed on a liquid crystal display device, or an image distributed by digital terrestrial broadcasting may be displayed on a liquid crystal display device. In this case, when displaying an image captured using a camera or an image distributed by broadcasting on a liquid crystal display device, it is necessary to rotate the image by a given angle (e.g., 90°, 180°, or 270°).
However, it is difficult to extract only data of pixels in a specific area after compression using technologies disclosed in JP-A-1-112377 and JP-A-2001-257888. When rotating an image, since the image data of the image after the rotation process is stored in a memory, a work area is necessary for the rotation process. According to the technologies disclosed in JP-A-1-112377 and JP-A-2001-257888, it is necessary to provide a memory which stores data of pixels of at least one screen. Therefore, the capacity of the memory must be increased.